The sides of a rectangular park are in the ratio 3 : 2 and its area is 21,600 sq. mts. The cost of fencing it at Rs.2.50 per metre is


A) Rs.1500

B) Rs. 600

C) Rs.1200

D) Rs.1800

Correct Answer:
A) Rs.1500

Description for Correct answer:
Let the length of rectangular part be 3x

Let the breadth of the rectangular part be 2x

Area = \( \Large 3x \times 2x = 6x^{2} \)

\( \Large 6x^{2} = 21600 \)

\( \Large x^{2} = 3600 => x = \sqrt{3600}=60 \)

Length = \( \Large 3 \times 60 \) = 180 m.

Breadth =\( \Large 2 \times 60 \) = 120 m.

Perimeter \( \Large 2 \left(l+b\right) = 2 \left(180+120\right) \) = 600 m.

Fencing 600m. at Rs.2.50 per metre.

=\( \Large 600 \times 2.50 \) = Rs.1500

Part of solved Area and perimeter questions and answers : >> Elementary Mathematics >> Area and perimeter








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